[1] Univ York, Martin House Res Ctr, Dept Hlth Sci, York YO10 5DD, England
[2] Univ York, Dept Hlth Sci, York YO10 5DD, England
[3] Univ York, Social Policy Res Unit, York YO10 5DD, England
[4] Univ Hull, Hull York Med Sch, Kingston Upon Hull HU6 7RX, England
[5] Univ York, Ctr Hlth Econ, York YO10 5DD, England
[6] Bangor Univ, Sch Med & Hlth Sci, Bangor LL57 2EF, Wales
[7] Bradford Teaching Hosp NHS Fdn Trust, Bradford BD9 6RJ, England
[8] Univ Leeds, Leeds Inst Data Analyt, Sch Med, Leeds LS2 9NL, England
[9] Univ York, Ctr Reviews & Disseminat, York YO10 5DD, England
[10] Cardiff & Vale Univ Hlth Board, All Wales Paediat Palliat Care Network, Cardiff CF14 4XW, Wales
[11] Swansea Univ, Coll Human & Hlth Sci, Swansea SA2 8PP, Wales
[12] Manchester Univ NHS Fdn Trust, Manchester M13 9WL, England
[13] Kings Coll London, Cicely Saunders Inst, Bessemer Rd, London SE5 9PJ, England